_base_ = "../retinanet/retinanet_r50_fpn_1x_coco.py"
model = dict(
    bbox_head=dict(
        _delete_=True,
        type="GARetinaHead",
        num_classes=80,
        in_channels=256,
        stacked_convs=4,
        feat_channels=256,
        approx_anchor_generator=dict(
            type="AnchorGenerator",
            octave_base_scale=4,
            scales_per_octave=3,
            ratios=[0.5, 1.0, 2.0],
            strides=[8, 16, 32, 64, 128],
        ),
        square_anchor_generator=dict(
            type="AnchorGenerator",
            ratios=[1.0],
            scales=[4],
            strides=[8, 16, 32, 64, 128],
        ),
        anchor_coder=dict(
            type="DeltaXYWHBBoxCoder",
            target_means=[0.0, 0.0, 0.0, 0.0],
            target_stds=[1.0, 1.0, 1.0, 1.0],
        ),
        bbox_coder=dict(
            type="DeltaXYWHBBoxCoder",
            target_means=[0.0, 0.0, 0.0, 0.0],
            target_stds=[1.0, 1.0, 1.0, 1.0],
        ),
        loc_filter_thr=0.01,
        loss_loc=dict(
            type="FocalLoss", use_sigmoid=True, gamma=2.0, alpha=0.25, loss_weight=1.0
        ),
        loss_shape=dict(type="BoundedIoULoss", beta=0.2, loss_weight=1.0),
        loss_cls=dict(
            type="FocalLoss", use_sigmoid=True, gamma=2.0, alpha=0.25, loss_weight=1.0
        ),
        loss_bbox=dict(type="SmoothL1Loss", beta=0.04, loss_weight=1.0),
    )
)
# training and testing settings
train_cfg = dict(
    ga_assigner=dict(
        type="ApproxMaxIoUAssigner",
        pos_iou_thr=0.5,
        neg_iou_thr=0.4,
        min_pos_iou=0.4,
        ignore_iof_thr=-1,
    ),
    ga_sampler=dict(
        type="RandomSampler",
        num=256,
        pos_fraction=0.5,
        neg_pos_ub=-1,
        add_gt_as_proposals=False,
    ),
    assigner=dict(neg_iou_thr=0.5, min_pos_iou=0.0),
    center_ratio=0.2,
    ignore_ratio=0.5,
)
optimizer_config = dict(_delete_=True, grad_clip=dict(max_norm=35, norm_type=2))
